During a closing operation, a closing head can be moved towards a container. Obviously a reverse method of operation is also conceivable in which the container is raised to the closing head. A simultaneous movement of the container and the closing head is also conceivable.
The force from outside can be exerted directly onto the closing head via a control element that moves the closing head. Insofar as the container is moved, for example, from below towards the closing head and is placed against the closing head by way of its opening, the force from outside results from a control element that raises the container and as a result produces a corresponding counterforce at the fixed closing head.
DE102006035279 describes a closing machine for closing bottles or similar containers with closures in a manner along the lines of the foregoing in which different closing positions, each with a closing tool, are formed on a rotating rotor for securing the closure. Each closing position has, associated therewith, at least two closing tools that are held on a tool carrier. These closing tools are closing cones that are mounted so as to be rotatable in the tool carrier. By moving the tool carrier, the closing tools can be moved between an operating position and a standby position. In the operating position, the closing tool secures a closure to a respective container.
Comparable bottle closing machines are known in practice. In these known devices, an outside force acts on the closing head during bottle closure. In one example, which is described in DE102006035279, the tool carrier exerts this force onto the closing tool or the closing head. Such an impingement of force is necessary in order, on the one hand, to attach the closure in a fault-free manner on the container opening, for example by means of screw-connection.
On the other hand, during the closing operation, the pressure often rises inside the container such that the screw-connecting operation has to be completed with the application of increasing force. This means that the pressure exerted onto the closure, and hence also onto the bottle, has to remain high enough at the end of the displacement path to close the container in a fault-free manner.
Because of this requirement, a problem that arises in practice is that the pressure on the screw-type closure or on the container is made unnecessarily high at the beginning of the displacement path to ensure that sufficient force will remain for fault-free closure at the end of the displacement path. As the closing head or the container is acted upon by a force from outside, and because filled disposable bottles, such as those made of PET are not very stable while they are still open, this unnecessarily high force at the beginning of the displacement path creates the risk of canting, or perhaps even deforming, the bottle to be closed. In extreme cases, the entire bottle closing machine can be brought to a standstill.